Which of the following is an example of a chemical change?

1 In an alloy, zinc and copper are in the ratio 1 : 2. In the second alloy, the same elements are in the ratio 2 : 3. If these two alloys be mixed to form a new alloy in which two elements are in the ratio 5:8, the ratio of these two alloys in the new allow 2 Direction: Read the following information carefully and answer the questions that follow: P, V, X, A, D, I, K and U set out for trip for different number of days such as 2, 8, 11, 5, 6, 4, 7 and 3, they go to the trip in the same order but the order of n 3 X and Y are two alloys which are prepared by mixing zinc and aluminium in the ratio of 1 : 4 and 11 : 8 respectively. If equal quantities of alloys are melted to form a third alloy Z then what is the ratio of zinc and aluminium in alloy Z? 4 Study the following information carefully to answer these questions.A vehicle starts from point P and run 10 km towards North. It takes a right turn and runs 15 km. Now it runs 6 km after taking a left turn. Finally, it takes a left turn, runs 15 km and s 5 Suppose A is an abstract class, B is a concrete subclass of A, and both A and B have a default constructor. Which of the following is correct?1. A a = new A();2. A a = new B();3. B b = new A();4. B b = new B();